Epoxy coating compositions with improved weatherability

ABSTRACT

Solvent soluble epoxy-containing compositions prepared by polymerizing ethylenically unsaturated monomers such as alkyl acrylates in the presence of the reaction product of a liquid epoxy resin such as a diglycidyl ether of bisphenol A and acrylic acid and/or methacrylic acid. These compositions are useful in the preparation of coatings.

BACKGROUND OF THE INVENTION

The present invention is directed to epoxy resins having improved weathering properties.

Epoxy resin coatings, particularly aromatic epoxy resin coatings usually have poor weathering characteristics. The aliphatic based epoxy resins usually have relatively good weathering characteristics but are usually deficient in such properties as a combination of hardness and flexibility (toughness) and chemical, solvent, and moisture resistance.

The epoxy resin coatings of the present invention not only have good weathering properties, they also have sufficiently good properties in one or more of the following: chemical, solvent, and moisture resistance, hardness, adhesion, and flexibility.

SUMMARY OF THE INVENTION

The present invention pertains to a solvent soluble epoxy-containing composition which comprises the product obtained by reacting in the presence of a suitable quantity of a suitable vinyl polymerization catalyst so as to effect polymerization:

(A) the reaction product obtained by reacting in the presence of a suitable quantity of a suitable catalyst

(1) at least one material having from greater than 1 to about 4 ##STR1## per molecule wherein each R is independently hydrogen or a monovalent hydrocarbon group having from 1 to about 4 carbon atoms; X is --O--, --S-- or ##STR2## and wherein said material has an epoxide equivalent weight of from about 150 to about 400, preferably from about 180 to about 270; and

(2) at least one of acrylic acid or methacrylic acid;

wherein components (1) and (2) are present in a quantity which provides an equivalent ratio of acid groups from component (2) to epoxy groups from component (1) of from about 0.1:1 to less than about 0.5:1, preferably from about 0.2:1 to about 0.3:1; and

(B) at least one monomer having at least one polymerizable ethylenically unsaturated group per molecule and which optionally contains a hydroxyl or an epoxide group; and

wherein components (A) and (B) are employed in quantities such that the weight ratio vinyl monomers to epoxy resin varies from 0.4 to 2.5, preferably from 0.6 to 1.5.

The present invention also pertains to a curable composition which comprises

(I) the aforementioned epoxy-containing composition;

(II) optionally a suitable quantity of a suitable solvent system; and

(III) an effective quantity of a suitable curing agent and/or catalyst.

DETAILED DESCRIPTION OF THE INVENTION

Suitable materials having an average of from greater than 1 to about 4 ##STR3## per molecule include the glycidyl ethers, thioethers and esters of aromatic compounds having an average of from greater than 1 to about 4 --OH, --SH, --COOH or mixture of such groups per molecule. Particularly suitable are those compounds represented by the formulas ##STR4## wherein A is independently a divalent hydrocarbon group having from one to about 8 carbon atoms, --O--, --S--, --S--S--, ##STR5## each A' is independently a divalent hydrocarbon group having from one to about 8, preferably from 1 to about 4 carbon atoms; each R is independently hydrogen or a monovalent hydrocarbon group having from 1 to about 4 carbons; each X is independently hydrogen, bromine, chlorine or a hydrocarbon group having from one to about 8 carbon atoms; each Z is independently --O--, --S-- or ##STR6## n has a value of zero or 1; n' has an average value of from zero to about 5, preferably from zero to about 3; and m has an average value of from about 0.1 to about 4, preferably from about 0.8 to about 2.

Suitable polymerizable ethylenically unsaturated monomers which can be employed herein include, for example, C₁ -C₈ alkyl esters of acrylic and methacrylic acid; styrene and ring-substituted styrenes; vinyl and vinylidene halides; vinyl esters such as vinyl acetate, vinyl propionate, and the like; ethylene or propylene; dialkyl maleate or fumarate esters; acrylonitrile, mixtures thereof and the like.

Suitable catalysts for reacting the low equivalent weight epoxy resin with the acrylic or methacrylic acid include, for example, phosphines, phosphonium salts, tertiary amines, tertiary ammonium bases and salts, mixtures thereof and the like.

Suitable vinyl polymerization catalysts include, for example, benzoyl peroxide, peroxy ethers, and peroxy esters; and azo compounds such as azobis(isobutyronitrile), mixtures thereof and the like.

Suitable curing agents for the epoxy-containing material include, for example, polyamides, polyamidoamines, polyamines, polythiols, polycarboxylic acids, and carboxylic acid anhydrides, mixtures thereof and the like.

Suitable solvents which can be employed herein include, for example, aromatic hydrocarbons, ketones, esters, alcohols, and glycol ethers having boiling-points above 140° C., or which can be contained by a pressure vessel if their boiling point is below 140° C., mixtures thereof and the like.

In addition to the aforementioned components, the curable compositions of the present invention can include, if desired, pigments, dyes, fillers, flow control agents, fire retardant agents, mixtures thereof and the like.

The following examples are illustrative of the present invention, but are not to be construed as to limiting the scope thereof in any manner.

In the following examples, reference is made to acrylic resin and epoxy resin.

Acrylic resin means a resinous substance, soft or hard at room temperature, formed by the free-radical initiated polymerization of acrylic or methacrylic acid, their esters, or their nitriles with each other, singly, or with other vinyl monomers such as styrene, vinyl acetate, vinyl or vinylidene chloride, maleate esters, ethylene, and the like.

Epoxy resin means resinous substances characterized by containing from 1.0 to about 5, usually 2.0 to 3.5, oxirane groups per molecule, usually as the 2,3-epoxypropylether group. The resin may be a crystalline or amorphous solid, a syrup, or an oily liquid.

EXAMPLE 1

A two-liter spherical Pyrex® reaction vessel was equipped for mechanical stirring, temperature measurement and control, solvent reflux, and continuous reactants addition by means of a metering pump. To this vessel was charged the following: 452.5 gm of a liquid diglycidyl ether of bisphenol A having an average EEW of 181, 58.0 gm of glacial methacrylic acid, 6.0 gm of a 1% solution of p-methoxyphenol in methyl amyl ketone; and 0.77 gm of a 70% solution of ethyltriphenyl phosphonium acetate.acetic acid complex in methanol as a catalyst. The mixture was stirred and warmed slowly to 120° C., at which point the heat of reaction caused the temperature to rise further to about 135°. It then fell slowly back to 120° where it was held until 2.0 hours (7200 s) after the time it first reached 120° C. At this time the vessel contents were a thin, yellow clear liquid containing <0.05% by weight of methacrylic acid (by gas chromatography). This liquid was cooled, and when the temperature had fallen to 60° C., a mixture of 187 ml of n-butyl acrylate and 206 ml of methyl methacrylate was added and stirred in until a clear, light-yellow liquid solution of resin-in-monomers was obtained (˜1/2 hour, 1800 s). This solution was further cooled to <10° C., and 7.5 ml (7.8 gm) of tert-butyl perbenzoate was added and stirred in. The entire cold solution, 857 ml, was then decanted into a one-liter Pyrex® reservoir attached to the reaction vessel via a metering pump.

To the now-empty vessel was charged 368.4 gm of methyl n-amyl ketone. Stirring was begun, and heat was applied to bring the liquid temperature to 150° C. as quickly as possible. When the temperature was at 150° C., the resin/monomers feed was started by turning on the metering pump. The pump was adjusted so that feed was completed in 3 hours and 55 minutes (14100 s). The pump hold-up was 20 ml, so the net feed-volume was 837 ml, or about 878 gm. The temperature was held at 150°±2° C. for 2.0 hours (7200 s) after completion of the feed, then the polymer solution was cooled to room temperature and bottled.

It was analyzed and was found to have the following properties.

    ______________________________________                                         Appearance           Clear, yellow                                             Viscosity at 25° C.                                                                          6820 cps                                                  % non-volatiles as:                                                            acrylic resin, wt.   50.2                                                      epoxy resin, wt.     19.1                                                      Acrylic resin mol. wt.                                                         --M.sub.w            1.77 × 10.sup.5                                     --M.sub.n            1.33 × 10.sup.4                                     EEW, liquid basis    729                                                       EEW, solids basis    505                                                       ______________________________________                                    

From the above data it was possible to calculate that the acrylic resin (solids) had an epoxy (C₂ H₃ O) content of 1.98 weight percent and an EEW (epoxide equivalent weight) of 2171, and therefore was functional in epoxy groups to the extent of 6.1 per average polymer molecule: ##EQU1## that the acrylic copolymer resin crosslink density, (X)_(n), was two per average molecule, and that the average molecule had a degree of polymerization of 80-81 (D.P.=80-81).

EXAMPLES 2-4 AND COMPARATIVE EXPERIMENTS A-C

The solution prepared in Example 1 was made into clear, catalyzed epoxy coating formulations as shown in Table I. Also included are comparative coatings prepared from an epoxy resin which is a diglycidyl ether of bisphenol A having an average EEW of about 500-525 designated as DGEBA as a 70% solids solution in methyl n-amyl ketone.

                  TABLE I                                                          ______________________________________                                                EXAMPLE OR                                                                     COMPARATIVE EXPERIMENT NO.                                                       EX-             EX-         EX-                                                AM-    COMP.    AM-  COMP.  AM-  COMP.                                COMPO-   PLE    EXPT.    PLE  EXPT.  PLE  EXPT.                                NENTS    2      A        3    B      4    C                                    ______________________________________                                         Product from                                                                            21.0   --       21.0 --     21.0 --                                   Ex. 1, g                                                                       DGEBA    --     21.0     --   21.0   --   21.0                                 SOLUTION,                                                                      GCH ®                                                                                5.0    5.0     --   --     --   --                                   140.sup.1, g                                                                   VERSA-   --     --       11.5 11.5   --   --                                   MID ®                                                                      115 × 70.sup.2, g                                                        D.E.H. ® 29.sup.3                                                                   --     --       --   --      1.2  1.2                                 methyl ether                                                                             5.0    5.0      5.0  5.0    5.0  5.0                                 of propylene                                                                   glycol, g                                                                      methyl ethyl                                                                            quantity required to provide spray viscosity                          ketone, g                                                                               of 250-300 cP.                                                        ______________________________________                                          .sup.1 A polyamide curing agent having an amine hydrogen equivalent weigh      of about 175 available from General Mills as Versamid 140.                      .sup.2 A polyamide curing agent having an amine hydrogen equivalent           weight of about 375 available from General Mills.                              .sup.3 A polyamide curing agent having an amine hydrogen equivalent weigh      of about 29 available from The Dow Chemical Company.                     

The clear lacquer-like solutions were spread in even films on 4"×12" (10.16 cm×30.48 cm) 20-guage unpolished cold-rolled steel panels and allowed to cure in a vertical position for one week (604800 s) at 24°-27° C. They were then evaluated as shown in Table II.

The results demonstrate that the subject compositions are capable of being formulated to yield coatings having not only superior resistance to dulling and chalking but other properties equal or superior to those of conventional epoxy resin coatings.

                                      TABLE II                                     __________________________________________________________________________                   EXAMPLE OR COMPARATIVE EXPERIMENT NO.                                                 COMP.        COMP.        COMP.                                         EXAMPLE                                                                               EXPT. EXAMPLE                                                                               EXPT. EXAMPLE                                                                               EXPT.                           PROPERTY      2      A     3      B     4      C                               __________________________________________________________________________     GLOSS         excellent                                                                             good  excellent                                                                             very  excellent                                                                             very                                                              good         good                            HARDNESS, pencil                                                                             2H-3H  H-2H  F-H    2H    2H     H-2H                            ADHESION (dry)                                                                               100%   30%   100%   56%   100%   31%                             REVERSE IMPACT, in-lb                                                                        >180   >180  >120   >180  >200   >200                            cm-kg         >207   >207  >138   >207  >230   >230                            MEK DOUBLE RUBS                                                                              >200   >200  >200   100-125                                                                              >200   >200                            LOSS OF ADHESION,                                                                            16%    100%  55%    100%  100%   100%                            1 hour boiling water                                                           water immersion                                                                SALT FOG EXPOSURE,                                                                           3/4"   gross 1/2"   1/2"-3/4"                                                                            gross  11/2"-2"                        24 hours (86400 s)                                                                           (19 mm)                                                                               failure                                                                              (12.7 mm)                                                                             (12.7 mm-                                                                            failure                                                                               (25.4 mm-                                     creep in     creep  19 mm)       50.8 mm)                                      24 hrs.             creep        creep                           QUV EXPOSURE, glossy complete-                                                                            glossy complete-                                                                            glossy complete-                       500 hours            ly flat      ly flat      ly flat                         (1,800,000 s)                                                                  DRY FILM THICKNESS                                                             mils          1.2-1.4                                                                               1.2-1.3                                                                              1.0-1.4                                                                               1.1-1.3                                                                              1.1-1.4                                                                               1.0-1.3                         mm            0.03048-                                                                              0.03048-                                                                             0.0254-                                                                               0.02794-                                                                             0.02794-                                                                              0.0254-                                       0.03556                                                                               0.03302                                                                              0.03556                                                                               0.03302                                                                              0.03556                                                                               0.03302                         __________________________________________________________________________

EXAMPLES 5-8

Employing the procedure for Example 1, various compositions were prepared. The components and characteristics are given in Table III.

The purpose of this series of experiments was to demonstrate the preparation and use of a set of copolymer resins in which the molecular weight has been varied by varying the ratio of vinyl carboxylic acid equivalents to glycidyl ether equivalents, short of gellation.

This variable (carboxyl group/epoxy group) is believed to control the molecular weight of the resulting vinyl copolymer by controlling the number of branch sites in the copolymer backbone; i.e., more branch sites results in higher molecular weight copolymer.

When the acid/epoxy ratio in this series was increased to 0.50, the solution gelled during the vinyl polymerization.

                                      TABLE III                                    __________________________________________________________________________                              EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                   5      6      7      8                                __________________________________________________________________________     COMPONENTS                                                                     EPOXY RESIN.sup.1, g/equiv.                                                                             240/1.26                                                                              240/1.26                                                                              240/1.26                                                                              240/1.26                         METHACRYLIC ACID, g/equiv.                                                                              21.7/.252                                                                             30.7/.357                                                                             37.6/.437                                                                             48.5/.564                        ACID/EPOXY EQUIV. RATIO  0.2/1  0.283/1                                                                               0.346/1                                                                               0.4/1                            1% PHENOTHIAZINE IN METHYL                                                                              10     10     10     10                               AMYL KETONE, g                                                                 ETHYLTRIPHENYLPHOSPHONIUM                                                                               0.5    0.5    0.5    0.5                              ACETATE.ACETIC ACID COMPLEX, g                                                 SEC-BUTYL ACRYLATE, g    133    133    133    133                              STYRENE, g               84.8   84.8   84.8   84.8                             t-BUTYL PERBENZOATE, g/mole %.sup.2                                                                     12.2/2.90                                                                             12.8/2.90                                                                             13.3/2.91                                                                             13.7/2.84                        METHYL AMYL KETONE, g    200    204    207    213                              PROPERTIES                                                                     SOLUTION VISCOSITY, cps  328    757    1870   3910                             % NON-VOLATILES          68.8   69.1   69.1   69.2                             MOLECULAR WEIGHT OF THE COPOLYMER                                              --M.sub.w                1.08 × 10.sup.4                                                                 1.52 × 10.sup.4                                                                 2.5 × 10.sup.4                                                                  3.7 × 10.sup.4             --M.sub.n                7.1 × 10.sup.3                                                                  8.02 × 10.sup.3                                                                 9.45 × 10.sup.3                                                                 1.09 × 10.sup.4            ACRYLIC/EPOXY, wt. %     50/50  51/49  52/48  52/48                            (.sup.-f).sub.n of acrylic copolymers                                                                   3.2    4.0    5.4    4.9                              (.sup. --X).sub.n of acrylic copolymers                                                                 0.4    0.8    1.3    0.6                              EEW (total solids basis) 515    590    660    800                              __________________________________________________________________________      .sup.1 The epoxy resin was a diglycidyl ether of bisphenol A having an         average EEW of 190.                                                            .sup.2 a freeradical polymerization initiator; mol % is defined as             follows:                                                                       ##STR7##                                                                 

EXAMPLES 9-12 AND COMP. EXPT. D-G

The solution epoxy-containing polymers of Table III were made into clear, catalyzed epoxy coatings. The components and results are given in Table IV. For comparative purposes, coatings were also prepared from glycidyl ethers of bisphenol A having equivalent weights similar to those of the examples. These comparative epoxy resins are designated in the table as DGEBA. The mixtures were all diluted to a viscosity of 120-145 cps with methyl ethyl ketone. The films were cast onto 24-guage unpolished cold-rolled steel panels and cured by allowing them to stand for one week (604800 s) at 24°-27° C. The compositions and results are given in Table IV.

                                      TABLE IV                                     __________________________________________________________________________                           COMP.       COMP.       COMP.       COMP.                COMPONENTS &   EXAMPLE                                                                               EXPT.                                                                               EXAMPLE                                                                               EXPT.                                                                               EXAMPLE                                                                               EXPT.                                                                               EXAMPLE                                                                               EXPT.                PROPERTIES     9      D    10     E    11     F    12     G                    __________________________________________________________________________     COPOLYMER SOLUTION,                                                                           5/30.0 --   6/30.0 --   7/30.0 --   8/30.0 --                   EX. NO./g                                                                      GCH 14, g      7.48   7.48 6.57   6.57                                         DGEBA SOLUTION, g                                                                             --     30.0 --     30.0 --     30.0 --     30.0                 METHYL ETHER OF                                                                               5.0    5.0  5.0    5.0  5.0    5.0  5.0    5.0                  PROPYLENE GLYCOL, g                                                            CURED FILM PROPERTIES                                                          GLOSS          excellent                                                                             excellent                                                                           excellent                                                                             excellent                                                                           excellent                                                                             excellent                                                                           excellent                                                                             excellent            REVERSE IMPACT,                                                                in-lbs         3      130  120    110  140    140  130    140                  cm-kg          3.5    150  138    127  161    161  150    161                  FORWARD IMPACT,                                                                in-lbs         18     180  180    180  180    180  180    180                  cm-kg          20.7   207  207    207  207    207  207    207                  HARDNESS, pencil                                                                              2H     2H   2H     3H   F      2H   F      2H                   ADHESION, % retained                                                                          100    100  100    100  100    100  100    100                  MEK DOUBLE RUBS                                                                               >200   >200 >200   >200 >200   >200 >200   >200                 DRY FILM THICKNESS,                                                            mils           2      1.5  1.5    1.5  2      1.5  2      1.5                  mm             0.05   0.04 0.05   0.04 0.05   0.04 0.04   0.04                 GLOSS AFTER 1000 HRS                                                                          fair   flat fair   flat good   flat good   flat                 (3.6 × 10.sup.6 s)                                                       QUV exposure                                                                   __________________________________________________________________________

EXAMPLES 13-16

Employing the procedure for Example 1, various compositions were prepared. The components and results are given in Table V.

The purpose of this series of experiments was to demonstrate the preparation and use of a set of copolymer resins in which the molecular weight has been varied by varying the initiator concentration while holding the number of branch sites constant. Higher initiator concentrations result in shorter copolymer chains, hence fewer branch sites per molecule.

Comparison of the data of Table V with those of Table III demonstrates that variation of initiator concentration is the more effective means of obtaining high levels of epoxy functionality in the vinyl copolymer (f_(n)) without driving up viscosity excessively. Both methods, however, are practical and yield coatings having similar properties.

When the t-butyl perbenzoate concentration was reduced to 0.50 mol %, the copolymer solution gelled during polymerization.

                                      TABLE V                                      __________________________________________________________________________                              EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                   13     14     15     16                               __________________________________________________________________________     COMPONENTS                                                                     EPOXY RESIN.sup.1, g/equiv.                                                                             452.5/2.5                                                                             452.5/2.5                                                                             452.5/2.5                                                                             452.5/2.5                        METHACRYLIC ACID, g/equiv.                                                                              58/.674                                                                               58/.674                                                                               58/.674                                                                               58/.674                          ACID/EPOXY EQUIV. RATIO  .270   .270   .270   .270                             1% p-METHOXYPHENOL IN METHYL                                                                            6.0    6.0    6.0    6.0                              AMYL KETONE, g                                                                 ETHYLTRIPHENYLPHOSPHONIUM                                                                               0.77   0.77   0.77   0.77                             ACETATE.ACETIC ACID COMPLEX, g                                                 n-BUTYL ACRYLATE, g      167.5  167.5  167.5  167.5                            METHYL METHACRYLATE, g   206.3  206.3  206.3  206.3                            t-BUTYL PERBENZOATE, g/mole %.sup.2                                                                     7.8/0.95                                                                              15.6/1.95                                                                             23.4/2.88                                                                             31.2/3.85                        METHYL AMYL KETONE, g    370    372    375    379                              PROPERTIES                                                                     SOLUTION VISCOSITY, cps  1100   512    427    378                              % NON-VOLATILES          68.7   68.3   68.8   68.8                             MOLECULAR WEIGHT OF THE COPOLYMER                                              --M.sub.w                5.1 × 10.sup.4                                                                  1.6 × 10.sup.4                                                                  1.2 × 10.sup.4                                                                  9.6 × 10.sup.3             --M.sub.n                9.47 × 10.sup.3                                                                 6.8 × 10.sup.3                                                                  5.22 × 10.sup.3                                                                 4.66 × 10.sup.3            ACRYLIC/EPOXY, wt. %     49/51  50/50  50/50  50/50                            (.sup.-f).sub.n of acrylic copolymers                                                                   6.6    4.3    3.5    2.9                              ( .sup.--X).sub.n of acrylic copolymers                                                                 1.2    0.8    0.6    0.5                              EEW (total solids basis) 497    504    509    523                              __________________________________________________________________________      .sup.1 The epoxy resin was a diglycidyl ether of bisphenol A having an         average EEW of 181.                                                            .sup.2 See Table III.                                                    

EXAMPLES 17-28 AND COMP. EXPT. H-J

The solution epoxy-containing polymers were made into clear catalyzed epoxy coatings. The components and results are given in Table VI. For comparative purposes, a similar coating was prepared from a diglycidyl ether of bisphenol A epoxy resin having a similar epoxide equivalent weight. This epoxy resin used for control purposes is designated as DGEBA. The compositions and results are given in Table VI.

The overall properties of these coatings are generally equal or superior to the control, with much better resistance to dulling by ultraviolet light.

                                      TABLE VI                                     __________________________________________________________________________                                                        COMP.                                              EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXPT.                       COMPONENTS & PROPERTIES                                                                               17     18     19     20     H                           __________________________________________________________________________     COPOLYMER SOLUTION, EX. NO./g                                                                         13/21.0                                                                               14/21.0                                                                               15/21.0                                                                               16/21.0                                                                               --                          DGEBA SOLUTION, g      --     --     --     --     21.0                        METHYL ETHER OF PROPYLENE                                                                             5.0    5.0    5.0    5.0    5.0                         GLYCOL, g                                                                      CURING AGENT, type     GCH14.sup.1                                                                           GCH14  GCH14  GCH14  GCH14                       g                      5.0    5.0    5.0    5.0    5.0                         METHYL ETHYL KETONE                                                            GLOSS                  excellent                                                                             excellent                                                                             excellent                                                                             excellent                                                                             good                        HARDNESS, pencil       2H-3H  2H     2H     2H     H-2H                        ADHESION (DRY), % retention                                                                           100    100    100    100    30                          REVERSE IMPACT, in-lbs >180   >180   >180   >180   >180                        cm-kg                  >207   >207   >207   >207   >207                        MEK DOUBLE RUBS        >200   >200   >200   >200   >200                        LOSS OF ADHESION AFTER IMMERSION                                                                      39     89     92     47     100                         FOR 1 HOUR (3600 s) IN BOILING                                                 WATER, %                                                                       SALT-FOG EXPOSURE FOR 24 HOURS                                                                        0.75"  0.75"  0.75"  0.75"  gross                       (86400 s)              (19.05 mm)                                                                            (19.05 mm)                                                                            (19.05 mm)                                                                            (19.05 mm)                                                                            failure                                            creep  creep  creep  creep                              EXPOSURE TO QUV FOR 500 HRS                                                                           low gloss                                                                             medium medium low gloss                                                                             flat                        (1.8 × 10.sup.6 s)      gloss  gloss                                     __________________________________________________________________________                                                        COMP.                                              EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXPT.                       COMPONENTS & PROPERTIES                                                                               21     22     23     24     I                           __________________________________________________________________________     COPOLYMER SOLUTION, EX. NO./g                                                                         13/21.0                                                                               14/21.0                                                                               15/21.0                                                                               16/21.0                                                                               --                          DGEBA SOLUTION, g      --     --     --     --     21.0                        METHYL ETHER OF PROPYLENE                                                                             5.0    5.0    5.0    5.0    5.0                         GLYCOL, g                                                                      CURING AGENT, type     V115X70.sup.2                                                                         V115X70                                                                               V115X70                                                                               V115X70                                                                               V115X70                     g                      11.5   11.5   11.5   11.5   11.5                        METHYL ETHYL KETONE                                                            GLOSS                  very good                                                                             very good                                                                             fair   good   very good                   HARDNESS, pencil       F-H    2H     2H     F      2H                          ADHESION (DRY), % retention                                                                           100    100    100    100    56                          REVERSE IMPACT, in-lbs 50     70     60     70     180                         cm-kg                  58     81     69     87     207                         MEK DOUBLE RUBS        >200   >200   >200   >200   <125                        LOSS OF ADHESION AFTER IMMERSION                                                                      <5     65     <5     34     100                         For 1 HOUR (3600 s) IN BOILING                                                 WATER, %                                                                       SALT-FOG EXPOSURE FOR 24 HOURS                                                                        0.5"   0.5"   0.5"   0.5"   0.5"                        (86400 s)              (12.7 mm)                                                                             (12.7 mm)                                                                             (12.7 mm)                                                                             (12.7 mm)                                                                             (12.7 mm)                                          creep  creep  creep  creep  creep                       EXPOSURE TO QUV FOR 500 HRS                                                                           low gloss                                                                             low gloss                                                                             low gloss                                                                             low gloss                                                                             flat                        (1.8 × 10.sup.6 s)                                                       __________________________________________________________________________                                                        COMP.                                              EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXPT.                       COMPONENTS & PROPERTIES                                                                               25     26     27     28     J                           __________________________________________________________________________     COPOLYMER SOLUTION, EX. NO./g                                                                         13/21.0                                                                               14/21.0                                                                               15/21.0                                                                               16/21.0                                                                               --                          DGEBA SOLUTION, g      --     --     --     --     21.0                        METHYL ETHER OF PROPYLENE                                                                             5.0    5.0    5.0    5.0    5.0                         GLYCOL, g                                                                      CURING AGENT, type     D.E.H. 29.sup.3                                                                       D.E.H. 29                                                                             D.E.H. 29                                                                             D.E.H. 29                                                                             D.E.H. 29                   g                      1.2    1.2    1.2    1.2    1.2                         METHYL ETHYL KETONE                                                            GLOSS                  excellent                                                                             excellent                                                                             excellent                                                                             excellent                                                                             very good                   HARDNESS, pencil       2H-3H  H-2H   2H-3H  H-2H   H-2H                        ADHESION (DRY), % retention                                                                           100    100    100    100    31                          REVERSE IMPACT, in-lbs 40     70     <20    30     >180                        MEK DOUBLE RUBS        >200   >200   >200   >200   >200                        LOSS OF ADHESION AFTER IMMERSION                                                                      10     100    100    100    100                         FOR 1 HOUR (3600 s) IN BOILING                                                 WATER, %                                                                       SALT-FOG EXPOSURE FOR 24 HOURS                                                                        1"     1"     1"     1"     gross                       (86400 s)              (25.4 mm)                                                                             (25.4 mm)                                                                             (25.4 mm)                                                                             (25.4 mm)                                                                             failure                                            creep  creep  creep  creep                              EXPOSURE TO QUV FOR 500 HRS                                                                           low gloss                                                                             low gloss                                                                             very low                                                                              low gloss                                                                             flat                        (1.8 × 10 s)                   gloss                                     __________________________________________________________________________      .sup.1 Curing agent GCH14 was a polyamide having an amine hydrogen             equivalent weight of about 175 available from General Mills as Versamid        114.                                                                           .sup.2 Curing agent V115X70 was a polyamide having an amine hydrogen           equivalent weight of about 375 available from General Mills as VERSAMIDE       ® 115X70.                                                                  .sup.3 D.E.H. ® 29 was a polyamine having an amine hydrogen equivalen      weight of about 29 available from The Dow Chemical Company.              

EXAMPLES 28-31

Employing the procedure for Example 1, various compositions were prepared. The components and characteristics are given in Table VII.

In this series of copolymers the molecular weight of the diglycidyl ether resin was increased until gellation of the copolymer solution occurred. The highest molecular-weight diglycidyl ether that could be used was about 760.

                                      TABLE VII                                    __________________________________________________________________________                              EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                   28     29     30     31                               __________________________________________________________________________     COMPONENTS                                                                     EPOXY RESIN.sup.1, g/equiv.                                                                             425/2.35                                                                              498.1/2.25                                                                            548.9/1.95                                                                            610.6/1.60                       , EEW                    181    221    281    381                              METHACRYLIC ACID, g/equiv.                                                                              58/.674                                                                               52.2/.607                                                                             45.2/.526                                                                             37.1/.431                        ACID/EPOXY EQUIV. RATIO  .287   .270   .270   .269                             1% P-METHOXYPHENOL IN METHYL                                                                            6.0    6.5    7.0    7.6                              AMYL KETONE, g                                                                 ETHYLTRIPHENYLPHOSPHONIUM                                                                               0.77   0.84   0.89   1.00                             ACETATE.ACETIC ACID COMPLEX, g                                                 n-BUTYL ACRYLATE, g      167.5  150.8  130.7  107.2                            METHYL METHACRYLATE, g   206.3  183.4  158.9  130.4                            t-BUTYL PERBENZOATE, g/mole %.sup.2                                                                     23.4/2.89                                                                             21.1/2.92                                                                             18.3/2.92                                                                             15/2.92                          METHYL AMYL KETONE, g    375    376    377    370                              PROPERTIES                                                                     SOLUTION VISCOSITY, cps  427    665    1100   3790                             % NON-VOLATILES          68.8   68.5   68.2   68.0                             MOLECULAR WEIGHT OF THE COPOLYMER                                              --M.sub.w                1.2 × 10.sub.4                                                                  1 × 10.sup.4                                                                    1.1 × 10.sup.4                                                                  1.5 × 10.sup.4             --M.sub.n                5.22 × 10.sup.3                                                                 5.4 × 10.sup.3                                                                  4.91 × 10.sup.3                                                                 5.67 × 10.sup.3            ACRYLIC/EPOXY, wt. %     50/50  45/55  39/61  32/68                            ( .sup.-f).sub.n of acrylic copolymer                                                                   3.5    3.6    2.5    3.0                              (.sup.--X).sub.n of acrylic copolymer                                                                   0.6    0.7    0.5    0.6                              EEW (total solids basis) 509    577    685    810                              __________________________________________________________________________      .sup.2 See Table III.                                                    

EXAMPLES 32-43

Employing the procedure for Examples 2-4, coatings were prepared from the epoxy-containing polymers prepared in Examples 28-31. Methyl ethyl ketone was added to each formulation in a quantity sufficient to provide the coating with a viscosity of 125-140 cps. The formulation and results are given in Table VIII.

It is noteworthy that when the EEW of the copolymer resin (total resin solids) passes from 685 to 810 a sharp deterioration in several properties is observed; viz., gloss retention, solvent resistance, and salt-fog resistance. An EEW less than about 700, and preferably less than about 600, is therefore desirable.

                                      TABLE VIII                                   __________________________________________________________________________                            EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                            COMPONENTS & PROPERTIES                                                                               32     33     34     35                                 __________________________________________________________________________     COPOLYMER SOLUTION, EX. NO./g                                                                         9/20.7 10/23.5                                                                               11/27.9                                                                               12/33                              METHYL ETHER OF PROPYLENE                                                                             5.0    5.0    5.0    5.0                                GLYCOL, g                                                                      CURING AGENT, type     GCH14.sup.1                                                                           GCH14  GCH14  GCH14                              g                      5.0    5.0    5.0    5.0                                GLOSS                  excellent                                                                             excellent                                                                             excellent                                                                             excellent                          HARDNESS, pencil       2H     2H     2H-3H  2H                                 ADHESION (DRY), % retention                                                                           100    100    100    100                                REVERSE IMPACT, in-lbs 150    >180   >180   >180                               cm-kg                  173    >207   >207   >207                               MEK DOUBLE RUBS        >200   >200   >200   100                                LOSS OF ADHESION AFTER IMMERSION                                                                      92     100    100    100                                FOR 1 HOUR (3600 s) IN BOILING                                                 WATER, %                                                                       SALT-FOG EXPOSURE FOR 24 HOURS                                                                        0.75"  0.5"   1"     1"                                 (86400 s)              (19.05 mm)                                                                            (12.7 mm)                                                                             (25.4 mm)                                                                             (25.4 mm)                                                 creep  creep  creep  creep                              EXPOSURE TO QUV FOR 500 HRS                                                                           fair   fair   fair   low                                (1.8 × 10.sup.6 s)                                                                              gloss  gloss  gloss  gloss                              __________________________________________________________________________                            EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                            COMPONENTS & PROPERTIES                                                                               36     37     38     39                                 __________________________________________________________________________     COPOLYMER SOLUTION, EX. NO./g                                                                         9/20.7 10/23.5                                                                               11/27.9                                                                               12/33.0                            METHYL ETHER OF PROPYLENE                                                                             5.0    5.0    5.0    5.0                                GLYCOL, g                                                                      CURING AGENT, type     V115X70.sup.2                                                                         V115X70                                                                               V115X70                                                                               V115X70                            g                      11.5   11.5   11.5   11.5                               GLOSS                  fair   excellent                                                                             excellent                                                                             excellent                          HARDNESS, pencil       2H     H      H      H                                  ADHESION (DRY), % retention                                                                           100    100    100    100                                REVERSE IMPACT, in-lbs 60     >180   >180   >180                               cm-kg                  69     >207   >207   >207                               MEK DOUBLE RUBS        >200   >200   200    100                                LOSS OF ADHESION AFTER IMMERSION                                                                      <5     10     <5     97                                 FOR 1 HOUR (3600 s) IN BOILING                                                 WATER, %                                                                       SALT-FOG EXPOSURE FOR 24 HOURS                                                                        0.5"   0.5"   0.75"  1"                                 (86400 s)              (12.7 mm)                                                                             (12.7 mm)                                                                             (19.05 mm)                                                                            (25.4 mm)                                                 creep  creep  creep  creep                              EXPOSURE TO QUV FOR 500 HRS                                                                           low    fair   low    good                               (1.8 × 10.sup.6 s)                                                                              gloss  gloss  gloss  gloss                              __________________________________________________________________________                            EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                            COMPONENTS & PROPERTIES                                                                               40     41     42     43                                 __________________________________________________________________________     COPOLYMER SOLUTION, EX. NO./g                                                                         9/20.7 10/23.5                                                                               11/27.9                                                                               12/33.0                            METHYL ETHER OF PROPYLENE                                                                             5.0    5.0    5.0    5.0                                GLYCOL, g                                                                      CURING AGENT, type     D.E.H. ® 29.sup.3                                                                 D.E.H. ® 29                                                                       D.E.H. ® 29                                                                       D.E.H. ® 29                    g                      1.2    1.2    1.2    1.2                                GLOSS                  excellent                                                                             excellent                                                                             excellent                                                                             excellent                          HARDNESS, pencil       2H-3H  3H     2H-3H  2H                                 ADHESION (DRY), % retention                                                                           100    100    100    100                                REVERSE IMPACT, in-lbs <20    110    130    >180                               cm-kg                  <23    127    150    >207                               MEK DOUBLE RUBS        >200   >200   190    175                                LOSS OF ADHESION AFTER IMMERSION                                                                      100    100    100    100                                FOR 1 HOUR (3600 s) IN BOILING                                                 WATER, %                                                                       SALT-FOG EXPOSURE FOR 24 HOURS                                                                        1"     1"     1"     gross                              (86400 s)              (25.4 mm)                                                                             (25.4 mm)                                                                             (25.4 mm)                                                                             failure                                                   creep  creep  creep                                     EXPOSURE TO QUV FOR 500 HRS                                                                           low    fair   good   low                                (1.8 × 10.sup.6 s)                                                                              gloss  gloss  gloss  gloss                              __________________________________________________________________________      .sup.1 Curing agent GCH14 was a polyamide having an amine hydrogen             equivalent weight of about 175 available from General Mills as Versamid        140.                                                                           .sup.2 Curing agent V115X70 was a polyamide having an amine hydrogen           equivalent weight of about 375 available from General Mills as VERSAMIDE       ® 115X70.                                                                  .sup.3 D.E.H. ® 29 was a polyamine having an amine hydrogen equivalen      weight of about 29 available from The Dow Chemical Company.              

EXAMPLES 44-48

Employing the procedure of Example 1, various compositions were prepared. The components and characteristics are given in Table IX.

The purpose of this series of copolymers was the demonstration of film improvements by incorporation of an hydroxyl-functional vinyl monomer into the copolymer.

                                      TABLE IX                                     __________________________________________________________________________                               EXAMPLE                                                                               EXAMPLE EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                           44     45      46     47     48                      __________________________________________________________________________     COMPONENTS                                                                     EPOXY RESIN.sup.1, g/equiv.                                                                              1200/6.63                                                                             400/2.21                                                                               400/2.21                                                                              400/2.21                                                                              400/2.21                METHACRYLIC ACID, g/equiv.                                                                               153.5/1.78                                                                            51.2/.60                                                                               51.2/.60                                                                              51.2/.60                                                                              51.2/.60                ACID/EPOXY EQUIV. RATIO   .269   .269    .269   .269   .269                    1% PHENOTHIAZINE IN METHYL                                                                               28.1   9.4     9.4    9.4    9.4                     AMYL KETONE, g                                                                 ETHYLTRIPHENYLPHOSPHONIUM 2.5    0.83    0.83   0.83   0.83                    ACETATE.ACETIC ACID COMPLEX, g                                                 n-BUTYL ACRYLATE, g       493    154     144    123    82                      STYRENE, g                597    199     199    199    199                     2-HYDROXYPROPYL ACRYLATE, g                                                                              0      10.3    20.6   41.2   82.4                    t-BUTYL PERBENZOATE, g/mole %.sup.2                                                                      65.9/2.88                                                                             22.0/2.89                                                                              22.0/2.89                                                                             22.0/2.90                                                                             22.0/2.91               METHYL AMYL KETONE, g     1040   343     343    343    343                     PROPERTIES                                                                     SOLUTION VISCOSITY, cps   822    1130    1180   1410   2030                    % NON-VOLATILES           70.5   70      70     70     70                      MOLECULAR WEIGHT OF THE COPOLYMER                                              --M.sub.w                 1.2 × 10.sup.4                                                                  2.2 × 10.sup.4                                                                   1.9 × 10.sup.4                                                                  2.3 × 10.sup.4                                                                  2.1 ×                                                                    10.sup.4                --M.sub.n                 7.15 × 10.sup.3                                                                 8.78 × 10.sup.3                                                                  8.49 × 10.sup.3                                                                 8.53 × 10.sup.3                                                                 8.79 ×                                                                   10.sup.3                ACRYLIC/EPOXY, wt. %      52/48  52/48   52/48  52/48  52/48                   (.sup.-f).sub.n of acrylic copolymer                                                                     3.4    4.2     4.2    4.2    4.2                     (.sup.--X).sub.n of acrylic copolymer                                                                    0.7    0.8     0.8    0.8    0.8                     EEW (total solids basis)  560    568     565    560    575                     __________________________________________________________________________      .sup.1 The epoxy resin was a diglycidyl ether of bisphenol A having an         average EEW of 181.                                                            .sup.2 See Table III.                                                    

EXAMPLES 49-63

Employing the procedure of Examples 2-4, coatings were prepared from the epoxy-containing polymers prepared in Table IX. Methyl ethyl ketone was added to each formulation in a quantity sufficient to provide the coating with a viscosity of 125-140 cps. The results are given in Table X.

In this series progressively larger amounts of 2-hydroxypropyl acrylate were substituted for n-butyl acrylate in the vinyl monomer recipe to improve copolymer resin/hardener compatibility. The results are improved dry-film clarity and gloss and reduced surface oiliness, if the 2-hydroxypropyl acrylate weight concentration in the vinyl monomers recipe exceeds about ten percent.

                                      TABLE X                                      __________________________________________________________________________                            EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                     COMPONENTS & PROPERTIES                                                                               49     50     51     52     53                          __________________________________________________________________________     COPOLYMER SOLUTION, EX. NO./g                                                                         44/21.0                                                                               45/21.0                                                                               46/21.0                                                                               47/21.0                                                                               48/21.0                     METHYL ETHER OF PROPYLENE                                                                             5.0    5.0    5.0    5.0    5.0                         GLYCOL, g                                                                      CURING AGENT, type     GCH14.sup.1                                                                           GCH14  GCH14  GCH14  GCH14                       g                      5.0    5.0    5.0    5.0    5.0                         GLOSS                  good   excellent                                                                             excellent                                                                             excellent                                                                             excellent                   HARDNESS, pencil       H      H      H      2H     H                           ADHESION (DRY), % retention                                                                           100    100    100    100    100                         REVERSE IMPACT, in-lbs 180    >180   180    180    180                         cm-kg                  207    >207   207    207    207                         MEK DOUBLE RUBS        >200   >200   >200   >200   >200                        LOSS OF ADHESION AFTER IMMERSION                                                                      61     86     86     96     44                          FOR 1 HOUR (3600 s) IN BOILING                                                 WATER, %                                                                       SALT-FOG EXPOSURE FOR 24 HOURS                                                 0.75"                  0.75"  0.75"  0.5"   0.75"                              (86400 s)              (19.05 mm)                                                                            (19.05 mm)                                                                            (19.05 mm)                                                                            (12.7 mm)                                                                             (19.05 mm)                                         creep  creep  creep  creep  creep                       EXPOSURE TO QUV FOR 500 HRS                                                                           medium medium medium low    medium                      (1.8 × 10.sup.6 s)                                                                              gloss  gloss  gloss  gloss  gloss                       FILM CLARITY           clear  clear  clear  clear  clear                       FILM SURFACE OILINESS  oily   slightly                                                                              none   none   none                                                      oily                                             __________________________________________________________________________                            EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                     COMPONENTS & PROPERTIES                                                                               54     55     56     57     58                          __________________________________________________________________________     COPOLYMER SOLUTION, EX. NO./g                                                                         44/21.0                                                                               45/21.0                                                                               46/21.0                                                                               47/21.0                                                                               48/21.0                     METHYL ETHER OF PROPYLENE                                                                             5.0    5.0    5.0    5.0    5.0                         GLYCOL, g                                                                      CURING AGENT, type     V115X70.sup.2                                                                         V115X70                                                                               V115X70                                                                               V115X70                                                                               V115X70                     g                      11.5   11.5   11.5   11.5   11.5                        GLOSS                  excellent                                                                             excellent                                                                             excellent                                                                             excellent                                                                             excellent                   HARDNESS, pencil       H      F-H    2H     F      H-2H                        ADHESION (DRY), % retention                                                                           100    100    100    100    100                         REVERSE IMPACT, in-lbs 30     50     80     110    120                         cm-kg                  35     58     92     127    138                         MEK DOUBLE RUBS        100    >200   100    100    150                         LOSS OF ADHESION AFTER IMMERSION                                                                      10     <5     32     32     55                          FOR 1 HOUR (3600 s) IN BOILING                                                 WATER, %                                                                       SALT-FOG EXPOSURE FOR 24 HOURS                                                                        1"     0.5"   gross  0.75"  0.5"                        (86400 s)              (25.4 mm)                                                                             (12.7 mm)                                                                             failure                                                                               (19.05 mm)                                                                            (12.7 mm)                                          creep  creep         creep  creep                       EXPOSURE TO QUV FOR 500 HRS                                                                           low gloss                                                                             low gloss                                                                             lost   low gloss                                                                             medium                      (1.8 × 10.sup.6 s)                           gloss                       FILM CLARITY           cloudy clear  clear  clear  clear                       FILM SURFACE OILINESS  oily   slightly                                                                              none   none   none                                                      oily                                             __________________________________________________________________________     EXAMPLE                EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                            COMPONENTS & PROPERTIES                                                                               59     60     61     62     63                          __________________________________________________________________________     COPOLYMER SOLUTION, EX. NO./g                                                                         44/21.0                                                                               45/21.0                                                                               46/21.0                                                                               47/21.0                                                                               48/21.0                     METHYL ETHER OF PROPYLENE                                                                             5.0    5.0    5.0    5.0    5.0                         GLYCOL, g                                                                      CURING AGENT, type     D.E.H. ® 29.sup.3                                                                 D.E.H. ® 29                                                                       D.E.H. ® 29                                                                       D.E.H. ® 29                                                                       D.E.H. ® 29             g                      1.2    1.2    1.2    1.2    1.2                         GLOSS                  good   good   excellent                                                                             excellent                                                                             excellent                   HARDNESS, pencil       H-2H   H-2H   2H     2H     2H                          ADHESION (DRY), % retention                                                                           100    100    100    100    100                         REVERSE IMPACT, in-lbs <20    <20    <20    <20    <20                         cm-kg                  <23    <23    <23    <23    <23                         MEK DOUBLE RUBS        >200   >200   >200   >200   >200                        LOSS OF ADHESION AFTER IMMERSION                                                                      100    100    100    100    100                         FOR 1 HOUR (3600 s) IN BOILING                                                 WATER, %                                                                       SALT-FOG EXPOSURE FOR 24 HOURS                                                                        1"     1"     1"     gross  gross                       (86400 s)              (25.4 mm)                                                                             (25.4 mm)                                                                             (25.4 mm)                                                                             failure                                                                               failure                                            creep  creep  creep                                     EXPOSURE TO QUV FOR 500 HRS                                                                           medium medium medium medium medium-                     (1.8 × 10.sup.6 s)                                                                              gloss  gloss  gloss  gloss  good gloss                  FILM CLARITY           faint  clear  clear  clear  clear                                              haze                                                    FILM SURFACE OILINESS  oily   oily   faint  none   none                        __________________________________________________________________________      .sup.1 Curing agent GCH14 was a polyamide having an amine hydrogen             equivalent weight of about 175 available from General Mills as Versamid        140.                                                                           .sup.2 Curing agent V115X70 was a polyamide having an amine hydrogen           equivalent weight of about 375 available from General Mills as VERSAMIDE       ® 115X70.                                                                  .sup.3 D.E.H. ® 29 was a polyamide having an amine hydrogen equivalen      weight of about 29 available from The Dow Chemical Company.              

EXAMPLES 64-66 AND COMP. EXPT. J

The procedure of Example 1 was employed in preparing the epoxy-containing polymers except that the polymerization temperature was varied. The components and results are given in Table XI.

Higher temperatures are seen to yield copolymers of narrower molecular weight distribution (M_(w) /M_(n)), a desirable property. A temperature of about 135° C. is the lowest practical.

                                      TABLE XI                                     __________________________________________________________________________                                                   COMP.                                                     EXAMPLE                                                                               EXAMPLE                                                                               EXAMPLE                                                                               EXPT.                                                     64     65     66     J                                __________________________________________________________________________     COMPONENTS                                                                     EPOXY RESIN.sup.1, g/equiv.                                                                             485.7/2.68                                                                            485.7/2.68                                                                            485.7/2.68                                                                            485.7/2.68                       METHACRYLIC ACID, g/equiv.                                                                              80/.93 80/.93 80/.93 80/.93                           ACID/EPOXY EQUIV. RATIO  .347   .347   .347   .347                             1% p-METHOXYPHENOL IN METHYL                                                   AMYL KETONE, g           6.6    6.6    6.6    6.6                              ETHYLTRIPHENYLPHOSPHONIUM                                                      ACETATE ·ACETIC ACID COMPLEX, g                                                                0.85   0.85   0.85   0.85                             n-BUTYL ACRYLATE, g      188    188    188    188                              METHYL METHACRYLATE, g   217.7  217.7  217.7  217.7                            t-BUTYL PERBENZOATE, g/mole %.sup.2                                                                     14.0/3.15                                                                             14.0/3.15                                                                             14.0/3.15                                                                             14.0/3.15                        METHYL AMYL KETONE, g    342    342    342 342                                 POLYMERIZATION TEMPERATURE, °C.                                                                  148    143    138    133                              PROPERTIES                                                                     SOLUTION VISCOSITY, cps  2110   4370   20900  gelled                           % NON-VOLATILES          70     70     70     --                               MOLECULAR WEIGHT OF THE COPOLYMER                                              --M.sub.w                5.0 × 10.sup.4                                                                  1.3 × 10.sup.5                                                                  3.0 × 10.sup.5                                                                  --                                --M.sub.n               7.42 × 10.sup.3                                                                 8.87 × 10.sup.3                                                                 8.82 × 10.sup.3                                                                 --                               ACRYLIC/EPOXY, wt. %     51/49  51/49  51/49  --                               .sup.-f.sub.n of acrylic copolymer                                                                      4.9    5.9    5.9    --                               .sup.--X.sub.n of acrylic copolymer                                                                     1.3    1.6    1.6    --                               EEW (total solids basis) 592    595    587    --                               __________________________________________________________________________      .sup.1 The epoxy resin was a diglycidyl ether of bisphenol A having an         average EEW of 181.                                                            .sup.2 See Table III.                                                    

EXAMPLE 67

The epoxy-methacrylic acid reaction was conducted as in Example 1. Then, this was mixed with the monomers and the mixture was fed over a period of 4 hours and 10 minutes (15000 s) at a solvent temperature of 120° C. The mixture was then stirred at 120° C. for an additional two hours (7200 s) to complete the polymerization. The composition and properties are given in the following Table XII.

This copolymer was prepared to illustrate the incorporation of additional epoxy functionality into the copolymer (the use of glycidyl methacrylate) and the use of a different solvent and a different polymerization initiator.

                  TABLE XII                                                        ______________________________________                                                               EXAMPLE                                                                        67                                                       ______________________________________                                         COMPONENTS                                                                     EPOXY RESIN.sup.1,g/equiv.                                                                             240/1.326                                              METHACRYLIC ACID, g/equiv.                                                                             30.7/.357                                              ACID/EPOXY EQUIV. RATIO .269                                                   1% p-METHOXYPHENOL IN METHYL                                                                           7.2                                                    AMYL KETONE, g                                                                 ETHYLTRIPHENYLPHOSPHONIUM                                                                              0.50                                                   ACETATE·ACETIC ACID COMPLEX, g                                        n-BUTYL ACRYLATE, g     137.3                                                  GLYCIDYL METHACRYLATE   72.0                                                   n-DODECANE-1-THIOL      1.2                                                    1-TERT-BUTYLAZO-1-CYANOCYCLO-                                                                          14.9/2.85                                              HEXANE g/mole %.sup.2                                                          METHYL ETHER OF PROPYLENE                                                                              284                                                    GLYCOL                                                                         PROPERTIES                                                                     SOLUTION VISCOSITY, cps not determined                                         % NON-VOLATILES         62                                                     MOLECULAR WEIGHT OF                                                            THE COPOLYMER                                                                  --M.sub.w               1.10 × 10.sup.4                                  --M.sub.n               5.14 × 10.sup.3                                  ACRYLIC/EPOXY, wt. %                                                           .sup.-f.sub.n of acrylic copolymer                                                                     3.7                                                    .sup.--X.sub.n of acrylic copolymer                                                                    0.7                                                    EEW (total solids basis)                                                                               359                                                    ______________________________________                                          .sup.1 The epoxy resin was a diglycidyl ether of bisphenol A having an         average EEW of 181.                                                            .sup.2 See Table III.                                                    

EXAMPLES 68-69

The procedure of Example 1 was employed using various epoxy resins. The components and results are given in the following Table XIII.

Both resins gave good coatings when cured with a polyamide.

                                      TABLE XIII                                   __________________________________________________________________________                              EXAMPLE                                                                               EXAMPLE                                                                 68     69                                             __________________________________________________________________________     COMPONENTS                                                                     EPOXY RESIN.sup.1, g/equiv.                                                                             237.sup.1 /1.43                                                                       511.3.sup.2 /2.86                              METHACRYLIC ACID, g/equiv.                                                                              24.6/.286                                                                             49.2/.572                                      ACID/EPOXY EQUIV. RATIO  .200   .200                                           1% PHENOTHIAZINE IN METHYL                                                                              10.0   --                                             AMYL KETONE, g                                                                 1% HYDROQUINONE IN METHYL                                                                               --     40.0                                           AMYL KETONE, g                                                                 ETHYLTRIPHENYLPHOSPHONIUM                                                                               0.50   1.37                                           ACETATE·ACETIC ACID COMPLEX, g                                        SEC-BUTYL ACRYLATE, g    133    --                                             n-BUTYL ACRYLATE, g      --     270.5                                          STYRENE, g               84.8   --                                             METHYL METHACRYLATE, g   --     191.6                                          t-BUTYL PERBENZOATE, g/mole %.sup.2                                                                     12.4/2.90                                                                             27.4/2.98                                      METHYL AMYL KETONE, g    200    411                                            PROPERTIES                                                                     SOLUTION VISCOSITY, cps  2790   2430                                           % NON-VOLATILES          68.7   69                                             MOLECULAR WEIGHT OF THE COPOLYMER                                              --M.sub.w                1.16 × 10.sup.4                                                                 2.9 × 10.sup.4                           --M.sub.n                8.17 × 10.sup.3                                                                 6.06 × 10.sup.3                          ACRYLIC/EPOXY, wt. %                                                           (.sup.-f).sub.n of acrylic copolymer                                                                    9.0    ˜8                                       (.sup.--X).sub.n of acrylic copolymer                                                                   2.4    ˜2                                       EEW (total solids basis) not det.                                                                              not det.                                       __________________________________________________________________________      .sup.1 The epoxy resin was the triglycidyl ether of                            tris(4hydroxyphenyl)methane having an average EEW of 166.                      .sup.2 The epoxy resin was the glycidyl ether of a phenolformaldehyde          novolac resin having an average epoxy functionality of about 3.5 and an        average EEW of about 179.                                                

EXAMPLE 70

A copolymer was prepared exactly as in Example 47, Table IX, except that, instead of 41.2 gm of 2-hydroxypropyl acrylate, 45.6 gm of 2-hydroxybutyl acrylate was used as part of the vinyl monomer mixture. The resulting copolymer solution had the following properties.

    ______________________________________                                         Solution viscosity, cps                                                                               779                                                     % Non-volatiles        68                                                      Mol. Wt. of the Copolymer                                                      --M.sub.w              1.74 × 10.sup.4                                   --M.sub.n              7.15 × 10.sup.3                                   Acrylic/Epoxy, wt. %   52/48                                                   (.sup.-f).sub.n of acrylic copolymer                                                                  3.5                                                     (-x).sub.n of acrylic copolymer                                                                       0.8                                                     EEW (total solids basis)                                                                              576                                                     ______________________________________                                    

The copolymers of Examples 47 and 70 were made into white enamels for use with polyamide curing agents as shown below. Also included was a conventional bisphenol A diglycidyl ether known as DER®671, for comparative purposes.

    ______________________________________                                         ENAMEL RECIPE                                                                               Resins of Conventional                                                         This Invention.sup.1                                                                     Epoxy Resin.sup.2                                       ______________________________________                                         Pigment Grind                                                                  Epoxy Resin    180.0 gm    168.0 gm                                            Solution                                                                       TiPure ® R-960                                                                            172.8 gm    172.8 gm                                            TiO.sub.2                                                                      Diluent                                                                        methyl ethyl ketone                                                                           sufficient to reduce the vis-                                                  cosity of the enamels to 300 cps.                               ______________________________________                                          .sup.1 at 70% solids                                                           .sup.2 at 75% solids in methyl ibutyl ketone                             

The pigment was dispersed in the epoxy resin solution by grinding the mixture for ten minutes (600 s) on a Cowles high-shear disperser.

To each enamel was added a solution of 18.0 gm of Versamid®1540 in 22.0 gm of Dowanol®PM glycol ether solvent. After thorough mixing, the enamels were allowed to stand for 1.0 hours (3600 s) at 25° C., then sprayed onto 24 gauge unpolished cold-rolled steel, 24 gauge phosphatized steel (Bonderite®40), and aluminum Q panels. The coatings were allowed to harden for one week at 25° C. The enamels were designated as follows:

Enamel based on 2-hydroxypropyl acrylate--I-A

Enamel based on 2-hydroxybutyl acrylate--I-B

Enamel based on conventional epoxy resin--I-C

In the same way, two more enamels were made for use with a different polyamide hardener, Versamid®115. In this case, only the experimental copolymer based on 2-hydroxypropyl acrylate was used.

    ______________________________________                                         ENAMEL RECIPE                                                                               Resins of Conventional                                                         This Invention                                                                           Epoxy Resin                                             ______________________________________                                         Pigment Grind                                                                  Epoxy Resin    170.0 gm    158.7 gm                                            Solution                                                                       TiPure ® R-960                                                                            214.0 gm    214.0 gm                                            TiO.sub.2                                                                      Diluent                                                                        methyl ethyl ketone                                                                           sufficient to reduce the vis-                                                  cosity of the enamels to 300 cps.                               ______________________________________                                    

To each of these enamels was added a solution of 59.5 gm of Versamid®115 dissolved in 50.0 gm of Dowanol®PM glycol ether and 26.9 gm of methyl ethyl ketone, with aging and spraying as before. Enamel designations were as follows.

Enamel based on 2-hydroxypropyl acrylate--IA

Enamel based on conventional epoxy resin--IIC

The five enamels at spraying had the properties shown in Table XIV.

                  TABLE XIV                                                        ______________________________________                                                  Value Property in Enamel                                              Enamel Property                                                                           IA      IB      IC      IIA   IIC                                   ______________________________________                                         color      white   white   white   white white                                 viscosity, cps                                                                            ˜300                                                                             ˜300                                                                             ˜300                                                                             ˜300                                                                           ˜300                            % non-volatiles                                                                           72      71      66      65    67                                    pigment/binder                                                                            1.20    1.20    1.20    1.20  1.20                                  resin/hardener                                                                            7.0     7.0     7.0     2.0   2.0                                   ______________________________________                                    

After curing for one week at 25° C., the coated panels were evaluated as shown in Tables XV, XVI and XVII.

                                      TABLE XV                                     __________________________________________________________________________     Cured Coating Properties Over 24-Guage                                         Unpolished Cold-Rolled Steel                                                                 Value Obtained with Enamel                                       Coating Property                                                                             IA     IB     IC     IIA    IIC                                  __________________________________________________________________________     60° Gloss, %                                                                          95     99     93     79     95                                   SURFACE OILINESS                                                                             none   none   none   none   none                                 IMPACT, FORWARD.sup.1                                                                        15     15     28     40     90                                   IMPACT, REVERSE.sup.1                                                                        <2     <2     <2     <20    30                                   ADHESION, %.sup.2                                                                            100    97     99     99     95                                   MEK DOUBLE-RUBS.sup.3                                                                        200    135    >200   >200   >200                                 1/8 in. (3.175 mm) conical                                                                   1/4"   1/8"   1/8"   <1/16" <1/16"                               mandrel bend.sup.4                                                                           (6.35 mm)                                                                             (3.175 mm)                                                                            (3.175 mm)                                                                            (1.5875 mm)                                                                           (1.5875 mm)                          DRY-FILM THICKNESS,                                                            mils          2-21/2 3-31/2 3-31/2 21/2-3 2                                    mm            0.0508-                                                                               0.0762-                                                                               0.0762-                                                                               0.0635-                                                                               0.0508                                             0.0635 0.0889 0.0889 0.0762                                      __________________________________________________________________________      .sup.1 Gardner impactor, inchlbs.                                              .sup.2 1.5 mil (0.0381 mm) crosshatch with tapepull                            .sup.3 to substrate                                                            .sup.4 length of crack at narrow end of bend                             

                  TABLE XVI                                                        ______________________________________                                         CURED COATING CORROSION-RESISTANCE.sup. 1 OVER                                 24-GUAGE BONDERITE ® 40                                                    Coating Value Obtained with Enamel                                             Property                                                                               IA       IB       IC     IIA    IIB                                    ______________________________________                                         creep from                                                                     scribe.sup. 2                                                                   3 days <1/32"   <1/32"   <1/32" <1/32" <1/32"                                 (259200 s)                                                                      7 days 1/32"    1/32"    1/32"  1/32"  1/32"                                  (604800 s)                                                                     21 days 1/4-3/8" 3/32"    1/2"   1/4"   1/4"                                   (1814400 s)                                                                    42 days 1/4-3/8" 1/8"     >1"    3/4"   1/8"                                   (3628800 s)                                                                    field                                                                          rusting                                                                         3 days none     none     slight none   none                                   (259200 s)                                                                      7 days none     none     severe none   none                                   (604800 s)                                                                     21 days none     none     severe none   none                                   (1814400 s)                                                                    42 days none     none     severe none   none                                   (3628800 s)                                                                    blisters                                                                        3 days none     none     many   none   none                                   (259200 s)                fine                                                  7 days none     none     many   none   none                                   (604800 s)                fine                                                 21 days none     none     many   few    none                                   (1814400 s)               fine   medium                                        42 days few      none     many   few    few                                    (3628800 s)                                                                            small             medium medium small                                  ______________________________________                                          .sup.1 5% saltfog at 95° F. for 1000 hours                              .sup.2 1/32" = 0.79375 mm; 1/4" = 6.35 mm; 3/4" = 19.05 mm; 1/16" = 1.587      mm                                                                             3/8" = 9.525 mm; 1" = 25.4 mm; 1/8" = 3.175 mm; 1/2" = 12.7 mm?          

                  TABLE XVII                                                       ______________________________________                                         Cured Coating Resistance to Dulling and Chalking in                            the QUV.sup.1  ® Over Aluminum Q-Panels                                                Value Obtained with Enamel                                         Property      IA     IB       IC   IIA    IIB                                  ______________________________________                                         60° GLOSS AFTER                                                          0 days       95     98       94   80     97                                    3 days (259200 s)                                                                           75     86       29   58     67                                    7 days (604800 s)                                                                           41     78       7    20     19                                   14 days (1209600 s)                                                                          15     30        6*  8       12*                                 21 days (1814400 s)                                                                          31      24*     5    5       7                                   28 days (2419200 s)                                                                           12*   21       3     5*     5                                   35 days (3024000 s)                                                                          11     19       3    7      --                                   42 days (3628800 s)                                                                          --     15       --   6      --                                   ______________________________________                                          *onset of chalking                                                             .sup.1 light/moisture cycle was 8.0 hours of light at 140° F.           (60° C.) and 4.0 hours of moisture at 125° F. (51.7°      C.).?                                                                    

EXAMPLE 71

A copolymer was prepared exactly as in Example 47, Table IX, except that 41.2 gm of 2-hydroxyethyl methacrylate was used in place of 41.2 gm of 2-hydroxypropyl acrylate. The resulting copolymer solution had the following properties.

    ______________________________________                                         solution viscosity, cps 1500                                                   % non-volatiles         69.7                                                   mol. wt. of the copolymer                                                      --M.sub.w               20,000                                                 --M.sub.n                7,300                                                 acrylic/epoxy, wt. %    52/48                                                  (.sup.-f).sub.n of acrylic polymer                                                                     3.7                                                    (-X).sub.n of acrylic polymer                                                                          0.9                                                    EEW (total solids basis)                                                                               562                                                    ______________________________________                                    

The resin was made into an enamel for use with Versamid®1540 and sprayed on metal panels as in Example 70. Cured coating properties are shown below in Tables XVII-XIX. The experimental enamel is designated as III-B and DER®671 control enamel as III-C.

                  TABLE XVIII                                                      ______________________________________                                         Cured Coating Properties Over 24-Guage                                         Unpolished Cold-Rolled Steel                                                   Coating Property                                                                               III-B         III-C                                            ______________________________________                                         60° GLOSS, %                                                                            89            93                                               SURFACE OILINESS                                                                               none          none                                             IMPACT, FORWARD 15            28                                               IMPACT, REVERSE <2            <2                                               ADHESION, %     99            99                                               MEK DOUBLE-RUBS >200          >200                                             1/8" (3.175 mm) 1/2" (12.7 mm)                                                                               <1/16"                                           MANDREL BEND    crack         (1.5875 mm)                                                                    crack                                            DRY FILM THICKNESS,                                                            mils            3-31/2        3-31/2                                           mm              0.0762-0.0889 0.0762-0.0889                                    ______________________________________                                    

                  TABLE XIX                                                        ______________________________________                                         Cured Coating Corrosion-Resistance Over 24-Guage                               Bonderite ® 40                                                                      Value Obtained with Enamel                                            Coating Property                                                                          III-B          III-C                                                ______________________________________                                         creep from scribe                                                               3 days(259200 s)                                                                         <1/32" (0.79375 mm)                                                                           <1/32" (0.79375 mm)                                   7 days(604800 s)                                                                         <1/32" (0.79375 mm)                                                                           1/32" (0.79375 mm)                                   21 days(1814400 s)                                                                        0-1/4" (0-6.35 mm)                                                                            1/2" (12.7 mm)                                       42 days(3628800 s)                                                                        1/4-3/8"       >1" (25.4 mm)                                                   (6.35-9.525 mm)                                                     field rusting                                                                   3 days(259200 s)                                                                         none           slight                                                7 days(604800 s)                                                                         none           severe                                               21 days(1814400 s)                                                                        none           severe                                               42 days(3628800 s)                                                                        none           severe                                               blisters                                                                        3 days(259200 s)                                                                         none           many fine                                             7 days(604800 s)                                                                         none           many fine                                            21 days(1814400 s)                                                                        none           many fine                                            42 days(3628800 s)                                                                        none           many medium                                          ______________________________________                                    

                  TABLE XX                                                         ______________________________________                                         Cured Coating Resistance to Dulling and                                        Chalking in the QUV ® Over                                                 Aluminum Q Panels                                                                               Value Obtained with Enamel                                    Property           III-B  III-C                                                ______________________________________                                         60° gloss after                                                         0 days                 92     94                                               3 days    (259200 s)   61     29                                               7 days    (6048800 s)  29     7                                                14 days   (1209600 s)  12      6*                                              21 days   (1814400 s)  11     5                                                28 days   (2419200 s)   9*    3                                                35 days   (3024000 s)   8     3                                                42 days   (3628800 s)  --     --                                               ______________________________________                                          *onset of chalking                                                       

EXAMPLE 72

A copolymer was prepared exactly as in Example 47, Table IX, except that the methacrylic acid was first copolymerized with the other vinyl monomers, then this carboxylated copolymer solution was coupled to the bisphenol A diglycidyl ether resin. A comparison of the properties of the two products is given in Table XXI.

                  TABLE XXI                                                        ______________________________________                                         Comparison of Two Identical Copolymers                                         Made by Different Procedures                                                                   Value Obtained                                                                 with Copolymer of                                              Copolymer Property                                                                               Example 47 Example 72                                        ______________________________________                                         appearance        clear, amber                                                                              clear, amber                                      % non-volatiles   70         69.1                                              solution viscosity                                                                               1410 cps   2720 cps                                          mol. wt. of vinyl copolymer                                                    --M.sub.w         23,000     72,500                                            --M.sub.n         8,530      9,530                                             EEW, liquid basis 800        732                                               EEW, solids basis 560        506                                               (.sup.-f).sub.n of the copolymer                                                                 3.4        4.2                                               (-X).sub.n of the copolymer                                                                      0.8        1.0                                               ______________________________________                                    

The much higher ratio M_(w) /Mn in Example 72 results in a doubling of the viscosity (undesirable) with only a slight improvement in copolymer functionality, (f)_(n). 

I claim:
 1. A solvent soluble epoxy-containing composition which comprises the product obtained by reacting in the presence of a suitable quantity of a suitable vinyl polymerization catalyst so as to effect polymerization(A) the reaction product obtained by reacting in the presence of a suitable quantity of a suitable catalyst(1) at least one material having from greater than 1 to about 4 ##STR8## per molecule wherein each R is independently hydrogen or a monovalent hydrocarbon group having from 1 to about 4 carbon atoms; X is --O--, --S-- or ##STR9## and wherein said material has an epoxide equivalent weight of from about 150 to about 400; and (2) at least one of acrylic acid or methacrylic acid; wherein components (1) and (2) are present in a quantity which provides an equivalent ratio of acid groups from component (2) to epoxy groups from component (1) of from about 0.1:1 to less than about 0.5:1; and (B) at least one monomer having at least one polymerizable ethylenically unsaturated group per molecule and which optionally contains a hydroxyl or an epoxide group; andwherein components (A) and (B) are employed in quantities such that the weight ratio of vinyl monomers to epoxy compound varies from about 0.4:1 to about 2.5:1.
 2. An epoxy-containing composition of claim 1 wherein(i) the equivalent weight of component (A-1) is from about 180 to about 270; (ii) the ratio of acid groups from component (A-2) to epoxy groups from component (A-1) is from about 0.2:1 to about 0.3:1; and (iii) components (A) and (B) are employed in quantities such that the weight ratio of vinyl monomers to epoxy compound is from about 0.6:1 to about 3.0:1.
 3. An epoxy-containing composition of claim 2 wherein(i) component (A-1) is a glycidyl ether of an aromatic dihydroxyl-containing compound or a mixture of such glycidyl ethers; and (ii) component (B) is styrene, n-butyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxybutyl methacrylate, or a mixture thereof.
 4. A curable composition which comprises(I) an epoxy-containing composition which comprises the product obtained by reacting in the presence of a suitable quantity of a suitable vinyl polymerization catalyst so as to effect polymerization(A) the reaction product obtained by reacting in the presence of a suitable quantity of a suitable catalyst(1) at least one material having from greater than 1 to about 4 ##STR10## per molecule wherein each R is independently hydrogen or a monovalent hydrocarbon group having from 1 to about 4 carbon atoms; X is --O--, --S-- or ##STR11## and wherein said material has an epoxide equivalent weight of from about 150 to about 400; and (2) at least one of acrylic acid or methacrylic acid; wherein components (1) and (2) are present in a quantity which provides an equivalent ratio of acid groups from component (2) to epoxy groups from component (1) of from about 0.1:1 to about 0.4:1; and (B) at least one monomer having at least one polymerizable ethylenically unsaturated group per molecule and which optionally contains a hydroxyl or an epoxide group; and wherein components (A) and (B) are employed in quantities such that the weight ratio of vinyl monomers to epoxy compound is from about 0.4:1 to about 2.5:1; (II) optionally a suitable quantity of a suitable solvent system for achieving the desired application viscosity; and (III) an effective quantity of a suitable curing agent and/or catalyst for curing the composition.
 5. A curable composition of claim 4 wherein(i) the equivalent weight of component (I-A-1) is from about 180 to about 270; (ii) the ratio of acid groups from component (I-A-2) to epoxy groups from component (I-A-1) is from about 0.2:1 to about 0.3:1; and (iii) components (I-A) and (I-B) are employed in quantities which provide a weight ratio of vinyl monomers to epoxy compound of from about 6:1 to about 1.5:1.
 6. A curable composition of claim 5 wherein(i) component (I-A-1) is a glycidyl ether of an aromatic dihydroxyl-containing compound or a mixture of such glycidyl ethers; (ii) component (I-B) is styrene, n-butyl acrylate, 2-ethylhexyl acrylate, hydroxyethyl acrylate, hydroxybutyl acrylate, hydroxybutyl methacrylate or a mixture thereof. 